Month: April 2016

Basic Antennas for VHF-UHF Field Communications part 1

You have your first radio for some time now, you want to increase its performance in the field and also make a better radio kit for it. If you haven’t heard or read yet, the three most important words in radio communications are: Antenna, Antenna, Antenna

(which are followed by the next three: Location, Location, Location)

So, let’s see what your starter antenna options are . And that means simple, economic, easy to deploy -or even make- radio antennas for the VHF and UHF bands.

 

The Groundplane

It is the antenna that uses an artificial “ground” to work. In a base antenna the “ground” is the 3 or 4 radials that extend from its base. In a mobile (car) antenna the “ground” is defined by the car’s metallic body.

So a way for a ready-made option is to take a mobile antenna (that is already pre-tuned) and create its ground yourself.

One option is to get a magnetic base antenna and nail a metal sheet on top of a pole. This can be a lid of a paint can, a cookie baking tray etc etc. Then you stick the magnetic mount antenna on top.

Continue reading “Basic Antennas for VHF-UHF Field Communications part 1”

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Notable Notes 3: A Look at AC Inverters for Off-Grid Power

Starting with a Note… I started this Notes series as a way to redirect readers to worthwhile articles and info sources. Sort of what you do when you share a post in Facebook. I strive for original content, so this method allows me to avoid informing readers of the good stuff out there without having to synthesize a new article of my own.

 

On the subject matter now, recently I stumbled on 2 articles on Inverters and the way to apply them for off-grid (read that as emergency also) power. They are on the Off-Grid HAM blog. Check them out!

AC Inverters For Off Grid Power, Part 1

AC Inverters For Off Grid Power, Part 2

Οι Μπαταρίες ΑΑ και ο Ασύρματος σας

Κατά κανόνα υπάρχουν μπαταριοθήκες ΑΑ & ΑΑΑ που αντικαθιστούν την κανονική μπαταρία για τους περισσότερους ασύρματους χειρός. Οπότε είναι καλό να έχουμε μια σαν εφεδρική πηγή ενέργειας, αλλά θα πρέπει να την δοκιμάσουμε εν λειτουργία πρώτα.

Και αυτό γιατί:

  1. Το βολτάζ των επαναφορτιζόμενων και των αλκαλικών μπαταριών ΑΑ είναι διαφορετικό και μπορεί ο ασύρματος μας να μη δουλεύει με έναν από τους δύο αυτούς τύπους.
  2. Συνήθως οι ασύρματοι χειρός κατεβάζουν ισχύ όταν χρησιμοποιούν τέτοιες μπαταρίες γιατί αυτές δεν έχουν την δύναμη να αντέξουν το φορτίο σε πλήρη ισχύ.

Διαβάστε περισσότερα στο blog μας GreekPreparedness

 

Random Thoughts on the BAO(feng)s

If there was a plan for little green Martians to conquer the earth, they would hide inside the Baofeng (UV-5R) radios and then pop out the same exact moment all around the world.

 

And those being so popular and cheap are two of the reasons for trashing them around the web. But are they…

 

Glorified FRS radios or Incentives for new HAMs?

 

Among the preparedness and survivalist communities the BAOs are prevalent. And I do not think there is anyone that has a second radio and it is not a UV-5R. so even the advanced HAMs among us could not resist the temptation of the cheap and “easy” radio.

Continue reading “Random Thoughts on the BAO(feng)s”

New Batterypack and Custom UV-5R Battery Eliminator

This is a continuation of two other projects the External Battery Pack for our handheld radios and an improvement on the Battery Eliminator we did for the Bao.

web-IGP3058

The Battery-Pack / Powerbank

This is a smaller size using two 18650 Lithium-ion rechargables to get the same voltage as the original Baofeng battery.

We have an affinity for the 18650 batteries, mainly because they are easy to handle, they lead the battery technology at the moment, can be cross loaded to other devices such as USB powerbanks, and we have a plenty of, since we are into flashlights too.

Continue reading “New Batterypack and Custom UV-5R Battery Eliminator”

The AA Batteries and Your Radio

Luckily most handheld radios and some QRP Rigs (Low Power shortwave radios) have an alternate AA battery option. It is prudent to include a AA case for any radio you own, but DO TEST it first.

Do not make the assumption that all will work fine, there are two hidden bugs particular to any radio.

These are:

– Voltage incompatibility depending on the type of batteries you use.

– The radio dropping its power on AA batteries.

 

So in the past few days we have been testing our Baofeng with various kind of AAA batteries options. Also Kenwood has details enough on final power out in the manual of the TH-F6 handheld that we also own. To summarize both:

Continue reading “The AA Batteries and Your Radio”